Provided below are ELISA kits targeting frizzled related protein, a human protein encoded by FRZB. This protein is 325 amino acids long, with a mass of 36.3 kDa, and is a member of the Secreted frizzled-related protein (sFRP) family. This is reported to be a secreted protein. There is a noted implication in Osteoarthritis 1. Other alias names for this protein include: secreted frizzled-related protein 3, frezzled, frizzled homolog-related, frizzled-related protein 1, FRE, FRITZ, and FRP-3.